In a conventional prior disposition, each unit cell of the storage battery is enclosed in a case, and a plurality of cells, and thus a plurality of cases, are assembled together in a frame which generally contains about four to six cells. The battery is made up of several frames clamped together against a wall by means of an assembly bar co-operating with tie bars.
In a prior system of this nature, cell cases are made of metal and the frames are made of wood. Within the frames, the cases do not stand on the bottoms of the frames but are suspended from the side walls by studs projecting from the faces of the cases of the cells, with the studs penetrating into corresponding holes in the side walls of the frames. This disposition serves firstly to prevent the cases from standing on the bottom and secondly to keep the cases spaced apart by appropriate gaps. This disposition is made necessary by the metal nature of the cases in order to isolate them from one another which is necessary if conducting paths may be produced between the cases by dirt, objects, etc.
However, it is now possible to make cases of molded plastic material which means that it is possible to design other dispositions for the frames avoiding certain insulating constraints and consequently, in particular, enabling bulk to be reduced.
Thus, a disposition is known in which a plurality of cells: e.g. four, five, or six; are received in a single one-piece plastic case. In this case there is no need for a frame. This disposition considerably reduces bulk, but it suffers from the drawback of requiring an entire one-piece case to be replaced with all of its cells in the event of a single cell becoming faulty.
In another disposition, each cell is situated in a plastic case which includes half dovetails on four of its vertical sides, thereby enabling an indefinite sequence of such cases to be assembled together by sliding assembly tongues over pairs of meeting half-dovetails on each side of a pair of cases placed adjacent to each other, and by preventing the cases from moving vertically relative to one another by folding over the bottom ends of the tongues against the bottom ends of the dovetails, with the top ends of the tongues being previously curved. At each end of a sequence formed in this way, e.g. a sequence of five cases, a plate including a handle for transport purposes is slid over the two half-dovetails situated on either side of the end face of the end case.
This disposition also avoids the use of a frame and makes it possible to reduce bulk while still retaining the possibility of interchanging a single cell without having to change a plurality of cells, as in the preceding disposition. However, this disposition requires a plurality of small pieces for assembly purposes, and such pieces may firstly be mislaid, and secondly they lengthen assembly time. Further, the half dovetails molded on the plastic cases do not always have sufficient mechanical strength.
The object of the present invention is to provide a support frame for storage battery cells which are individually enclosed in respective cases of molded insulating synthetic material, providing reduced bulk compared with frames for metal-cased storage batteries, and requiring no assembly pieces for assembling n cells in a frame and for holding them therein (other than the inter-cell electrical connection strips), and enabling the frame to be turned upsidedown without causing the cases to fall out therefrom. In addition, the frame provides considerable mechanical strength.